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V4L2-CTL(1)			  User Commands 		     V4L2-CTL(1)

NAME
     v4l2-ctl - An application to control video4linux drivers

SYNOPSIS
     v4l2-ctl [-h] [-d <dev>] [many other options]

DESCRIPTION
     The  v4l2-ctl  tool  is  used to control video4linux devices, either video,
     vbi, radio or swradio, both input and output. It is able to control  almost
     any aspect of such devices covering the full V4L2 API.

OPTIONS
     -d, --device <dev>
	    Use  device <dev> as the V4L2 device.  if <dev> starts with a digit,
	    then /dev/video<dev> is used Otherwise if -z was specified	earlier,
	    then  <dev> is the entity name or interface ID (if prefixed with 0x)
	    as found in the topology of the  media  device  with  the  bus  info
	    string as specified by the -z option.

     -v, --verbose
	    Turn on verbose reporting.

     --version
	    Show version information.

     -w, --wrapper
	    Use the libv4l2 wrapper library for all V4L2 device accesses. By de-
	    fault  v4l2-ctl  will directly access the V4L2 device, but with this
	    option all access will go via this wrapper library.

     -h, --help
	    Prints the help message.

     --help-io
	    Prints the help message for all options that get/set/list inputs and
	    outputs, both video and audio.

     --help-misc
	    Prints the help message for miscellaneous options.

     --help-overlay
	    Prints the help message for all options  that  get/set/list  overlay
	    and framebuffer formats.

     --help-sdr
	    Prints  the  help message for all options that get/set/list software
	    defined radio formats.

     --help-selection
	    Prints the help message for all options that  deal	with  selections
	    (cropping and composing).

     --help-stds
	    Prints  the  help  message for all options that deal with SDTV stan-
	    dards and Digital Video timings.

     --help-streaming
	    Prints the help message for all options that deal with streaming.

     --help-subdev
	    Prints the help message for all options that deal  with  v4l-subdevX
	    devices.

     --help-tuner
	    Prints  the  help  message for all options that deal with tuners and
	    modulators.

     --help-vbi
	    Prints the help message for all options that get/set/list  VBI  for-
	    mats.

     --help-vidcap
	    Prints the help message for all options that get/set/list video cap-
	    ture formats.

     --help-vidout
	    Prints the help message for all options that get/set/list video out-
	    put formats.

     --help-edid
	    Prints the help message for all options that get/set EDIDs.

     --help-all
	    Prints the help message for all options.

     --all  Display all information available.

     -C, --get-ctrl <ctrl>[,<ctrl>...]
	    Get the value of the controls [VIDIOC_G_EXT_CTRLS].

     -c, --set-ctrl <ctrl>=<val>[,<ctrl>=<val>...]
	    Set the value of the controls [VIDIOC_S_EXT_CTRLS].

     -D, --info
	    Show driver info [VIDIOC_QUERYCAP].

     -e, --out-device <dev>
	    Use device <dev> for output streams instead of the default device as
	    set   with	 --device.   If   <dev>   starts   with  a  digit,  then
	    /dev/video<dev> is used.  Otherwise if  -z	was  specified	earlier,
	    then  <dev> is the entity name or interface ID (if prefixed with 0x)
	    as found in the topology of the  media  device  with  the  bus  info
	    string as specified by the -z option.

     -E, --export-device <dev>
	    Use  device <dev> for exporting DMA buffers.  If <dev> starts with a
	    digit, then /dev/video<dev> is used.  Otherwise if -z was  specified
	    earlier,  then <dev> is the entity name or interface ID (if prefixed
	    with 0x) as found in the topology of the media device with	the  bus
	    info string as specified by the -z option.

     -z, --media-bus-info <bus-info>
	    Find the media device with the given <bus-info> string. If set, then
	    -d, -e and -E options can use the entity name or interface ID to re-
	    fer  to the device nodes. Example: v4l2-ctl -z platform:vivid-000 -d
	    vivid-000-vid-cap

     -k, --concise
	    Be more concise if possible.

     -l, --list-ctrls
	    Display all controls and their values [VIDIOC_QUERYCTRL].

     -L, --list-ctrls-menus
	    Display all controls and their menus [VIDIOC_QUERYMENU].

     -r, --subset <ctrl>[,<offset>,<size>]+
	    The subset of the N-dimensional array to get/set for control <ctrl>,
	    for every dimension an (<offset>, <size>) tuple is given.

     --list-devices
	    List all v4l devices. If -z was given, then list just the devices of
	    the media device with the bus info string as specified by the -z op-
	    tion.

     --log-status
	    Log the board status in the kernel log [VIDIOC_LOG_STATUS].

     --get-priority
	    Query the current access priority [VIDIOC_G_PRIORITY].

     --set-priority <prio>
	    Set the new access priority [VIDIOC_S_PRIORITY].  <prio> is 1 (back-
	    ground), 2 (interactive) or 3 (record).

     --silent
	    Only set the result code, do not print any messages.

     --sleep <secs>
	    Sleep <secs>, call QUERYCAP and close the file handle.

EXIT STATUS
     On success, it returns 0. Otherwise, it will return the error code.

EXAMPLES
     Query the device information of /dev/video1:

	  v4l2-ctl -d1 -D

     Stream video using MMAP stream I/O from /dev/video0:

	  v4l2-ctl -d0 --stream-mmap

     Stream one frame of video from /dev/video0 and store it in a file:

	  v4l2-ctl --stream-mmap --stream-count=1 --stream-to=file.raw

     Stream video from /dev/video0 and stream it over the network:

	  v4l2-ctl --stream-mmap --stream-to-host <hostname>

     Use 'qvidcap -p' on the host to view the video.

     Stream video from /dev/video0 using DMABUFs exported from /dev/video2:

	  v4l2-ctl --stream-dmabuf --export-device /dev/video2

     Stream video from a memory-to-memory device:

	  v4l2-ctl --stream-mmap --stream-out-mmap

     Stream video from a capture video device (/dev/video1) to an  output  video
     device (/dev/video2):

	  v4l2-ctl  -d1  --stream-mmap	--out-device  /dev/video2  --stream-out-
     dmabuf

BUGS
     This manual page is a work in progress.

     Bug reports or questions about this utility should be sent to the linux-me-
     dia@vger.kernel.org mailinglist.

v4l-utils 1.23.0		   March 2015			     V4L2-CTL(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=v4l2-ctl&sektion=1&manpath=FreeBSD+15.1-RELEASE+and+Ports.quarterly>

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